The volume of data in a computer system having storage systems has increased explosively, and a large number of storage systems for holding the data are now installed in the computer system. In such a computer system, it is sometimes necessary to implement one processing for a plurality of linked storage systems. Remote copying technology for avoiding data loss or interruption of business service, for example due to accidents or device failure, is used as a processing technology performed for such a link of a plurality of storage systems. The remote copying technology is disclosed, for example, in Japanese Patent Application Laid-open No. 11-85408.
With the remote copying technology, a first storage system stores data received from a host computer. The first storage system then transmits the data received from the host computer to the second storage system disposed in a physically remote location. As a result, the second storage system stores the data received from the first storage system. In a computer system employing the remote copying technology, data and processing thereof can be restored within a comparatively short period even if an accident or failure occurs. More specifically, in the computer system employing the remote copying technology, restoration from a failure can be performed by using data stored in the second storage system.
On the other hand, a logical partitioning technology for storage systems is used by which one storage system is logically partitioned in order to provide an adequate storage resource of input/output performance (IO performance) to a large number of host computers disposed in a computer system. The logical partitioning technology for storage systems is disclosed, for example, in Japanese Patent Application Laid-open No. 2005-222123. With the logical partitioning technology for storage systems, a plurality of logical storage systems comprising storage resources and cache memories different from those of the storage system itself can appear to the host computer and storage system of the link destination to be present in the storage system. As a result, it is possible to allocate storage resources and provide IO performance suitable for a plurality of present host computers.
When the logical partitioning technology for storage systems is applied to computer systems operated with a plurality of storage systems linked together, e.g., in a remote copying mode, the following problem is encountered. Thus, when a storage system that comprises a logical partitioning function (refereed to as “high-functionality storage system”) is to be linked to a storage system that does not comprise a logical partitioning function (referred Lo as “low-functionality storage system”), the low-functionality storage system cannot recognize the presence of logical storage systems that were logically partitioned in the high-functionality storage system, and the low-functionality storage system and high-functionality storage system cannot be linked correctly.
Likewise, the presence of logical storage systems sometimes cannot be recognized not only in the low-functionality storage system serving as an example of an external device, but also in other external devices such as management computers that are not associated with the logical partitioning function, and the processing cannot be executed adequately.